summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp_ipv4.c
Commit message (Collapse)AuthorAge
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-08-13
|\ | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/ethernet/cavium/Kconfig The cavium conflict was overlapping dependency changes. Signed-off-by: David S. Miller <davem@davemloft.net>
| * inet: fix possible request socket leakEric Dumazet2015-08-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit b357a364c57c9 ("inet: fix possible panic in reqsk_queue_unlink()"), I missed fact that tcp_check_req() can return the listener socket in one case, and that we must release the request socket refcount or we leak it. Tested: Following packetdrill test template shows the issue 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 +0 < S 0:0(0) win 2920 <mss 1460,sackOK,nop,nop> +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> +.002 < . 1:1(0) ack 21 win 2920 +0 > R 21:21(0) Fixes: b357a364c57c9 ("inet: fix possible panic in reqsk_queue_unlink()") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: Set sk_txhash from a random numberTom Herbert2015-07-29
| | | | | | | | | | | | | | | | | | | | | | This patch creates sk_set_txhash and eliminates protocol specific inet_set_txhash and ip6_set_txhash. sk_set_txhash simply sets a random number instead of performing flow dissection. sk_set_txash is also allowed to be called multiple times for the same socket, we'll need this when redoing the hash for negative routing advice. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: inet_twsk_deschedule factorizationEric Dumazet2015-07-09
|/ | | | | | | | | | | | | inet_twsk_deschedule() calls are followed by inet_twsk_put(). Only particular case is in inet_twsk_purge() but there is no point to defer the inet_twsk_put() after re-enabling BH. Lets rename inet_twsk_deschedule() to inet_twsk_deschedule_put() and move the inet_twsk_put() inside. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: remove redundant checks IIEric Dumazet2015-06-07
| | | | | | | | For same reasons than in commit 12e25e1041d0 ("tcp: remove redundant checks"), we can remove redundant checks done for timewait sockets. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: remove redundant checksEric Dumazet2015-06-04
| | | | | | | | | | | | | | | | | | | | | | | | | | tcp_v4_rcv() checks the following before calling tcp_v4_do_rcv(): if (th->doff < sizeof(struct tcphdr) / 4) goto bad_packet; if (!pskb_may_pull(skb, th->doff * 4)) goto discard_it; So following check in tcp_v4_do_rcv() is redundant and "goto csum_err;" is wrong anyway. if (skb->len < tcp_hdrlen(skb) || ...) goto csum_err; A second check can be removed after no_tcp_socket label for same reason. Same tests can be removed in tcp_v6_do_rcv() Note : short tcp frames are not properly accounted in tcpInErrs MIB, because pskb_may_pull() failure simply drops incoming skb, we might fix this in a separate patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: add tcpi_segs_in and tcpi_segs_out to tcp_infoMarcelo Ricardo Leitner2015-05-21
| | | | | | | | | | | | | | | | | | | | | | | | | This patch tracks the total number of inbound and outbound segments on a TCP socket. One may use this number to have an idea on connection quality when compared against the retransmissions. RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut These are a 32bit field each and can be fetched both from TCP_INFO getsockopt() if one has a handle on a TCP socket, or from inet_diag netlink facility (iproute2/ss patch will follow) Note that tp->segs_out was placed near tp->snd_nxt for good data locality and minimal performance impact, while tp->segs_in was placed near tp->bytes_received for the same reason. Join work with Eric Dumazet. Note that received SYN are accounted on the listener, but sent SYNACK are not accounted. Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: add rfc3168, section 6.1.1.1. fallbackDaniel Borkmann2015-05-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This work as a follow-up of commit f7b3bec6f516 ("net: allow setting ecn via routing table") and adds RFC3168 section 6.1.1.1. fallback for outgoing ECN connections. In other words, this work adds a retry with a non-ECN setup SYN packet, as suggested from the RFC on the first timeout: [...] A host that receives no reply to an ECN-setup SYN within the normal SYN retransmission timeout interval MAY resend the SYN and any subsequent SYN retransmissions with CWR and ECE cleared. [...] Schematic client-side view when assuming the server is in tcp_ecn=2 mode, that is, Linux default since 2009 via commit 255cac91c3c9 ("tcp: extend ECN sysctl to allow server-side only ECN"): 1) Normal ECN-capable path: SYN ECE CWR -----> <----- SYN ACK ECE ACK -----> 2) Path with broken middlebox, when client has fallback: SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) SYN -----> <----- SYN ACK ACK -----> In case we would not have the fallback implemented, the middlebox drop point would basically end up as: SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) SYN ECE CWR ----X crappy middlebox drops packet (timeout, rtx) In any case, it's rather a smaller percentage of sites where there would occur such additional setup latency: it was found in end of 2014 that ~56% of IPv4 and 65% of IPv6 servers of Alexa 1 million list would negotiate ECN (aka tcp_ecn=2 default), 0.42% of these webservers will fail to connect when trying to negotiate with ECN (tcp_ecn=1) due to timeouts, which the fallback would mitigate with a slight latency trade-off. Recent related paper on this topic: Brian Trammell, Mirja Kühlewind, Damiano Boppart, Iain Learmonth, Gorry Fairhurst, and Richard Scheffenegger: "Enabling Internet-Wide Deployment of Explicit Congestion Notification." Proc. PAM 2015, New York. http://ecn.ethz.ch/ecn-pam15.pdf Thus, when net.ipv4.tcp_ecn=1 is being set, the patch will perform RFC3168, section 6.1.1.1. fallback on timeout. For users explicitly not wanting this which can be in DC use case, we add a net.ipv4.tcp_ecn_fallback knob that allows for disabling the fallback. tp->ecn_flags are not being cleared in tcp_ecn_clear_syn() on output, but rather we let tcp_ecn_rcv_synack() take that over on input path in case a SYN ACK ECE was delayed. Thus a spurious SYN retransmission will not prevent ECN being negotiated eventually in that case. Reference: https://www.ietf.org/proceedings/92/slides/slides-92-iccrg-1.pdf Reference: https://www.ietf.org/proceedings/89/slides/slides-89-tsvarea-1.pdf Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mirja Kühlewind <mirja.kuehlewind@tik.ee.ethz.ch> Signed-off-by: Brian Trammell <trammell@tik.ee.ethz.ch> Cc: Eric Dumazet <edumazet@google.com> Cc: Dave That <dave.taht@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: provide SYN headers for passive connectionsEric Dumazet2015-05-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows a server application to get the TCP SYN headers for its passive connections. This is useful if the server is doing fingerprinting of clients based on SYN packet contents. Two socket options are added: TCP_SAVE_SYN and TCP_SAVED_SYN. The first is used on a socket to enable saving the SYN headers for child connections. This can be set before or after the listen() call. The latter is used to retrieve the SYN headers for passive connections, if the parent listener has enabled TCP_SAVE_SYN. TCP_SAVED_SYN is read once, it frees the saved SYN headers. The data returned in TCP_SAVED_SYN are network (IPv4/IPv6) and TCP headers. Original patch was written by Tom Herbert, I changed it to not hold a full skb (and associated dst and conntracking reference). We have used such patch for about 3 years at Google. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* inet: fix possible panic in reqsk_queue_unlink()Eric Dumazet2015-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ 3897.923145] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [ 3897.931025] IP: [<ffffffffa9f27686>] reqsk_timer_handler+0x1a6/0x243 There is a race when reqsk_timer_handler() and tcp_check_req() call inet_csk_reqsk_queue_unlink() on the same req at the same time. Before commit fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer"), listener spinlock was held and race could not happen. To solve this bug, we change reqsk_queue_unlink() to not assume req must be found, and we return a status, to conditionally release a refcount on the request sock. This also means tcp_check_req() in non fastopen case might or not consume req refcount, so tcp_v6_hnd_req() & tcp_v4_hnd_req() have to properly handle this. (Same remark for dccp_check_req() and its callers) inet_csk_reqsk_queue_drop() is now too big to be inlined, as it is called 4 times in tcp and 3 times in dccp. Fixes: fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp/dccp: get rid of central timewait timerEric Dumazet2015-04-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using a timer wheel for timewait sockets was nice ~15 years ago when memory was expensive and machines had a single processor. This does not scale, code is ugly and source of huge latencies (Typically 30 ms have been seen, cpus spinning on death_lock spinlock.) We can afford to use an extra 64 bytes per timewait sock and spread timewait load to all cpus to have better behavior. Tested: On following test, /proc/sys/net/ipv4/tcp_tw_recycle is set to 1 on the target (lpaa24) Before patch : lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0 419594 lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0 437171 While test is running, we can observe 25 or even 33 ms latencies. lpaa24:~# ping -c 1000 -i 0.02 -qn lpaa23 ... 1000 packets transmitted, 1000 received, 0% packet loss, time 20601ms rtt min/avg/max/mdev = 0.020/0.217/25.771/1.535 ms, pipe 2 lpaa24:~# ping -c 1000 -i 0.02 -qn lpaa23 ... 1000 packets transmitted, 1000 received, 0% packet loss, time 20702ms rtt min/avg/max/mdev = 0.019/0.183/33.761/1.441 ms, pipe 2 After patch : About 90% increase of throughput : lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0 810442 lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0 800992 And latencies are kept to minimal values during this load, even if network utilization is 90% higher : lpaa24:~# ping -c 1000 -i 0.02 -qn lpaa23 ... 1000 packets transmitted, 1000 received, 0% packet loss, time 19991ms rtt min/avg/max/mdev = 0.023/0.064/0.360/0.042 ms Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* tcp: md5: fix a typo in tcp_v4_md5_lookup()Eric Dumazet2015-04-09
| | | | | | | | | Lookup key for tcp_md5_do_lookup() has to be taken from addr_sk, not sk (which can be the listener) Fixes: fd3a154a00fb ("tcp: md5: get rid of tcp_v[46]_reqsk_md5_lookup()") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: coding style: comparison for inequality with NULLIan Morris2015-04-03
| | | | | | | | | | | | The ipv4 code uses a mixture of coding styles. In some instances check for non-NULL pointer is done as x != NULL and sometimes as x. x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: coding style: comparison for equality with NULLIan Morris2015-04-03
| | | | | | | | | | | | The ipv4 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-04-02
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/usb/asix_common.c drivers/net/usb/sr9800.c drivers/net/usb/usbnet.c include/linux/usb/usbnet.h net/ipv4/tcp_ipv4.c net/ipv6/tcp_ipv6.c The TCP conflicts were overlapping changes. In 'net' we added a READ_ONCE() to the socket cached RX route read, whilst in 'net-next' Eric Dumazet touched the surrounding code dealing with how mini sockets are handled. With USB, it's a case of the same bug fix first going into net-next and then I cherry picked it back into net. Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp: prevent fetching dst twice in early demux codeMichal Kubeček2015-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On s390x, gcc 4.8 compiles this part of tcp_v6_early_demux() struct dst_entry *dst = sk->sk_rx_dst; if (dst) dst = dst_check(dst, inet6_sk(sk)->rx_dst_cookie); to code reading sk->sk_rx_dst twice, once for the test and once for the argument of ip6_dst_check() (dst_check() is inline). This allows ip6_dst_check() to be called with null first argument, causing a crash. Protect sk->sk_rx_dst access by READ_ONCE() both in IPv4 and IPv6 TCP early demux code. Fixes: 41063e9dd119 ("ipv4: Early TCP socket demux.") Fixes: c7109986db3c ("ipv6: Early TCP socket demux") Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: tcp_syn_flood_action() can be staticEric Dumazet2015-03-29
| | | | | | | | | | | | | | | | | | | | | | After commit 1fb6f159fd21 ("tcp: add tcp_conn_request"), tcp_syn_flood_action() is no longer used from IPv6. We can make it static, by moving it above tcp_conn_request() Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Octavian Purdila <octavian.purdila@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: fix ipv4 mapped request socksEric Dumazet2015-03-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ss should display ipv4 mapped request sockets like this : tcp SYN-RECV 0 0 ::ffff:192.168.0.1:8080 ::ffff:192.0.2.1:35261 and not like this : tcp SYN-RECV 0 0 192.168.0.1:8080 192.0.2.1:35261 We should init ireq->ireq_family based on listener sk_family, not the actual protocol carried by SYN packet. This means we can set ireq_family in inet_reqsk_alloc() Fixes: 3f66b083a5b7 ("inet: introduce ireq_family") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: md5: get rid of tcp_v[46]_reqsk_md5_lookup()Eric Dumazet2015-03-24
| | | | | | | | | | | | | | | | | | | | | | With request socks convergence, we no longer need different lookup methods. A request socket can use generic lookup function. Add const qualifier to 2nd tcp_v[46]_md5_lookup() parameter. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: md5: remove request sock argument of calc_md5_hash()Eric Dumazet2015-03-24
| | | | | | | | | | | | | | | | | | | | | | Since request and established sockets now have same base, there is no need to pass two pointers to tcp_v4_md5_hash_skb() or tcp_v6_md5_hash_skb() Also add a const qualifier to their struct tcp_md5sig_key argument. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: md5: input path is run under rcu protected sectionsEric Dumazet2015-03-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | It is guaranteed that both tcp_v4_rcv() and tcp_v6_rcv() run from rcu read locked sections : ip_local_deliver_finish() and ip6_input_finish() both use rcu_read_lock() Also align tcp_v6_inbound_md5_hash() on tcp_v4_inbound_md5_hash() by returning a boolean. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: fix double request socket freeingFan Du2015-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Eric Hugne reported following error : I'm hitting this warning on latest net-next when i try to SSH into a machine with eth0 added to a bridge (but i think the problem is older than that) Steps to reproduce: node2 ~ # brctl addif br0 eth0 [ 223.758785] device eth0 entered promiscuous mode node2 ~ # ip link set br0 up [ 244.503614] br0: port 1(eth0) entered forwarding state [ 244.505108] br0: port 1(eth0) entered forwarding state node2 ~ # [ 251.160159] ------------[ cut here ]------------ [ 251.160831] WARNING: CPU: 0 PID: 3 at include/net/request_sock.h:102 tcp_v4_err+0x6b1/0x720() [ 251.162077] Modules linked in: [ 251.162496] CPU: 0 PID: 3 Comm: ksoftirqd/0 Not tainted 4.0.0-rc3+ #18 [ 251.163334] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 251.164078] ffffffff81a8365c ffff880038a6ba18 ffffffff8162ace4 0000000000009898 [ 251.165084] 0000000000000000 ffff880038a6ba58 ffffffff8104da85 ffff88003fa437c0 [ 251.166195] ffff88003fa437c0 ffff88003fa74e00 ffff88003fa43bb8 ffff88003fad99a0 [ 251.167203] Call Trace: [ 251.167533] [<ffffffff8162ace4>] dump_stack+0x45/0x57 [ 251.168206] [<ffffffff8104da85>] warn_slowpath_common+0x85/0xc0 [ 251.169239] [<ffffffff8104db65>] warn_slowpath_null+0x15/0x20 [ 251.170271] [<ffffffff81559d51>] tcp_v4_err+0x6b1/0x720 [ 251.171408] [<ffffffff81630d03>] ? _raw_read_lock_irq+0x3/0x10 [ 251.172589] [<ffffffff81534e20>] ? inet_del_offload+0x40/0x40 [ 251.173366] [<ffffffff81569295>] icmp_socket_deliver+0x65/0xb0 [ 251.174134] [<ffffffff815693a2>] icmp_unreach+0xc2/0x280 [ 251.174820] [<ffffffff8156a82d>] icmp_rcv+0x2bd/0x3a0 [ 251.175473] [<ffffffff81534ea2>] ip_local_deliver_finish+0x82/0x1e0 [ 251.176282] [<ffffffff815354d8>] ip_local_deliver+0x88/0x90 [ 251.177004] [<ffffffff815350f0>] ip_rcv_finish+0xf0/0x310 [ 251.177693] [<ffffffff815357bc>] ip_rcv+0x2dc/0x390 [ 251.178336] [<ffffffff814f5da3>] __netif_receive_skb_core+0x713/0xa20 [ 251.179170] [<ffffffff814f7fca>] __netif_receive_skb+0x1a/0x80 [ 251.179922] [<ffffffff814f97d4>] process_backlog+0x94/0x120 [ 251.180639] [<ffffffff814f9612>] net_rx_action+0x1e2/0x310 [ 251.181356] [<ffffffff81051267>] __do_softirq+0xa7/0x290 [ 251.182046] [<ffffffff81051469>] run_ksoftirqd+0x19/0x30 [ 251.182726] [<ffffffff8106cc23>] smpboot_thread_fn+0x153/0x1d0 [ 251.183485] [<ffffffff8106cad0>] ? SyS_setgroups+0x130/0x130 [ 251.184228] [<ffffffff8106935e>] kthread+0xee/0x110 [ 251.184871] [<ffffffff81069270>] ? kthread_create_on_node+0x1b0/0x1b0 [ 251.185690] [<ffffffff81631108>] ret_from_fork+0x58/0x90 [ 251.186385] [<ffffffff81069270>] ? kthread_create_on_node+0x1b0/0x1b0 [ 251.187216] ---[ end trace c947fc7b24e42ea1 ]--- [ 259.542268] br0: port 1(eth0) entered forwarding state Remove the double calls to reqsk_put() [edumazet] : I got confused because reqsk_timer_handler() _has_ to call reqsk_put(req) after calling inet_csk_reqsk_queue_drop(), as the timer handler holds a reference on req. Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Erik Hugne <erik.hugne@ericsson.com> Fixes: fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer") Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4: tcp: handle ICMP messages on TCP_NEW_SYN_RECV request socketsEric Dumazet2015-03-23
| | | | | | | | | | | | | | | | | | | | | | | | | | tcp_v4_err() can restrict lookups to ehash table, and not to listeners. Note this patch creates the infrastructure, but this means that ICMP messages for request sockets are ignored until complete conversion. New tcp_req_err() helper is exported so that we can use it in IPv6 in following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: convert syn_wait_lock to a spinlockEric Dumazet2015-03-23
| | | | | | | | | | | | | | | | | | | | This is a low hanging fruit, as we'll get rid of syn_wait_lock eventually. We hold syn_wait_lock for such small sections, that it makes no sense to use a read/write lock. A spin lock is simply faster. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: get rid of central tcp/dccp listener timerEric Dumazet2015-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | One of the major issue for TCP is the SYNACK rtx handling, done by inet_csk_reqsk_queue_prune(), fired by the keepalive timer of a TCP_LISTEN socket. This function runs for awful long times, with socket lock held, meaning that other cpus needing this lock have to spin for hundred of ms. SYNACK are sent in huge bursts, likely to cause severe drops anyway. This model was OK 15 years ago when memory was very tight. We now can afford to have a timer per request sock. Timer invocations no longer need to lock the listener, and can be run from all cpus in parallel. With following patch increasing somaxconn width to 32 bits, I tested a listener with more than 4 million active request sockets, and a steady SYNFLOOD of ~200,000 SYN per second. Host was sending ~830,000 SYNACK per second. This is ~100 times more what we could achieve before this patch. Later, we will get rid of the listener hash and use ehash instead. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: drop prev pointer handling in request sockEric Dumazet2015-03-20
| | | | | | | | | | | | | | | | | | | | | | When request sock are put in ehash table, the whole notion of having a previous request to update dl_next is pointless. Also, following patch will get rid of big purge timer, so we want to delete a request sock without holding listener lock. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: request sock should init IPv6/IPv4 addressesEric Dumazet2015-03-18
| | | | | | | | | | | | | | | | In order to be able to use sk_ehashfn() for request socks, we need to initialize their IPv6/IPv4 addresses. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: add IPv6 support to sk_ehashfn()Eric Dumazet2015-03-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intent is to converge IPv4 & IPv6 inet_hash functions to factorize code. IPv4 sockets initialize sk_rcv_saddr and sk_v6_daddr in this patch, thanks to new sk_daddr_set() and sk_rcv_saddr_set() helpers. __inet6_hash can now use sk_ehashfn() instead of a private inet6_sk_ehashfn() and will simply use __inet_hash() in a following patch. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: ip early demux should avoid request socketsEric Dumazet2015-03-16
| | | | | | | | | | | | | | | | | | | | When a request socket is created, we do not cache ip route dst entry, like for timewait sockets. Let's use sk_fullsock() helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: introduce ireq_familyEric Dumazet2015-03-12
| | | | | | | | | | | | | | | | Before inserting request socks into general hash table, fill their socket family. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | inet: get_openreq4() & get_openreq6() do not need listenerEric Dumazet2015-03-12
| | | | | | | | | | | | | | | | | | | | | | ireq->ir_num contains local port, use it. Also, get_openreq4() dumping listen_sk->refcnt makes litle sense. inet_diag_fill_req() can also use ireq->ir_num Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4: Create probe timer for tcp PMTU as per RFC4821Fan Du2015-03-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As per RFC4821 7.3. Selecting Probe Size, a probe timer should be armed once probing has converged. Once this timer expired, probing again to take advantage of any path PMTU change. The recommended probing interval is 10 minutes per RFC1981. Probing interval could be sysctled by sysctl_tcp_probe_interval. Eric Dumazet suggested to implement pseudo timer based on 32bits jiffies tcp_time_stamp instead of using classic timer for such rare event. Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ipv4: Use binary search to choose tcp PMTU probe_sizeFan Du2015-03-06
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Current probe_size is chosen by doubling mss_cache, the probing process will end shortly with a sub-optimal mss size, and the link mtu will not be taken full advantage of, in return, this will make user to tweak tcp_base_mss with care. Use binary search to choose probe_size in a fine granularity manner, an optimal mss will be found to boost performance as its maxmium. In addition, introduce a sysctl_tcp_probe_threshold to control when probing will stop in respect to the width of search range. Test env: Docker instance with vxlan encapuslation(82599EB) iperf -c 10.0.0.24 -t 60 before this patch: 1.26 Gbits/sec After this patch: increase 26% 1.59 Gbits/sec Signed-off-by: Fan Du <fan.du@intel.com> Acked-by: John Heffner <johnwheffner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: Namespecify TCP PMTU mechanismFan Du2015-02-09
| | | | | | | | | | | | | | | | Packetization Layer Path MTU Discovery works separately beside Path MTU Discovery at IP level, different net namespace has various requirements on which one to chose, e.g., a virutalized container instance would require TCP PMTU to probe an usable effective mtu for underlying tunnel, while the host would employ classical ICMP based PMTU to function. Hence making TCP PMTU mechanism per net namespace to decouple two functionality. Furthermore the probe base MSS should also be configured separately for each namespace. Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-02-05
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/vxlan.c drivers/vhost/net.c include/linux/if_vlan.h net/core/dev.c The net/core/dev.c conflict was the overlap of one commit marking an existing function static whilst another was adding a new function. In the include/linux/if_vlan.h case, the type used for a local variable was changed in 'net', whereas the function got rewritten to fix a stacked vlan bug in 'net-next'. In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next' overlapped with an endainness fix for VHOST 1.0 in 'net'. In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter in 'net-next' whereas in 'net' there was a bug fix to pass in the correct network namespace pointer in calls to this function. Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: tcp: get rid of ugly unicast_sockEric Dumazet2015-02-01
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit be9f4a44e7d41 ("ipv4: tcp: remove per net tcp_sock") I tried to address contention on a socket lock, but the solution I chose was horrible : commit 3a7c384ffd57e ("ipv4: tcp: unicast_sock should not land outside of TCP stack") addressed a selinux regression. commit 0980e56e506b ("ipv4: tcp: set unicast_sock uc_ttl to -1") took care of another regression. commit b5ec8eeac46 ("ipv4: fix ip_send_skb()") fixed another regression. commit 811230cd85 ("tcp: ipv4: initialize unicast_sock sk_pacing_rate") was another shot in the dark. Really, just use a proper socket per cpu, and remove the skb_orphan() call, to re-enable flow control. This solves a serious problem with FQ packet scheduler when used in hostile environments, as we do not want to allocate a flow structure for every RST packet sent in response to a spoofed packet. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: tcp: add per route congestion controlDaniel Borkmann2015-01-05
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This work adds the possibility to define a per route/destination congestion control algorithm. Generally, this opens up the possibility for a machine with different links to enforce specific congestion control algorithms with optimal strategies for each of them based on their network characteristics, even transparently for a single application listening on all links. For our specific use case, this additionally facilitates deployment of DCTCP, for example, applications can easily serve internal traffic/dsts in DCTCP and external one with CUBIC. Other scenarios would also allow for utilizing e.g. long living, low priority background flows for certain destinations/routes while still being able for normal traffic to utilize the default congestion control algorithm. We also thought about a per netns setting (where different defaults are possible), but given its actually a link specific property, we argue that a per route/destination setting is the most natural and flexible. The administrator can utilize this through ip-route(8) by appending "congctl [lock] <name>", where <name> denotes the name of a congestion control algorithm and the optional lock parameter allows to enforce the given algorithm so that applications in user space would not be allowed to overwrite that algorithm for that destination. The dst metric lookups are being done when a dst entry is already available in order to avoid a costly lookup and still before the algorithms are being initialized, thus overhead is very low when the feature is not being used. While the client side would need to drop the current reference on the module, on server side this can actually even be avoided as we just got a flat-copied socket clone. Joint work with Florian Westphal. Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-12-10
|\ | | | | | | | | | | | | | | | | | | Conflicts: drivers/net/ethernet/amd/xgbe/xgbe-desc.c drivers/net/ethernet/renesas/sh_eth.c Overlapping changes in both conflict cases. Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp: fix more NULL deref after prequeue changesEric Dumazet2014-12-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When I cooked commit c3658e8d0f1 ("tcp: fix possible NULL dereference in tcp_vX_send_reset()") I missed other spots we could deref a NULL skb_dst(skb) Again, if a socket is provided, we do not need skb_dst() to get a pointer to network namespace : sock_net(sk) is good enough. Reported-by: Dann Frazier <dann.frazier@canonical.com> Bisected-by: Dann Frazier <dann.frazier@canonical.com> Tested-by: Dann Frazier <dann.frazier@canonical.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Fixes: ca777eff51f7 ("tcp: remove dst refcount false sharing for prequeue mode") Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-11-29
|\ \ | |/
| * tcp: fix possible NULL dereference in tcp_vX_send_reset()Eric Dumazet2014-11-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit ca777eff51f7 ("tcp: remove dst refcount false sharing for prequeue mode") we have to relax check against skb dst in tcp_v[46]_send_reset() if prequeue dropped the dst. If a socket is provided, a full lookup was done to find this socket, so the dst test can be skipped. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=88191 Reported-by: Jaša Bartelj <jasa.bartelj@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Daniel Borkmann <dborkman@redhat.com> Fixes: ca777eff51f7 ("tcp: remove dst refcount false sharing for prequeue mode") Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: introduce SO_INCOMING_CPUEric Dumazet2014-11-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alternative to RPS/RFS is to use hardware support for multiple queues. Then split a set of million of sockets into worker threads, each one using epoll() to manage events on its own socket pool. Ideally, we want one thread per RX/TX queue/cpu, but we have no way to know after accept() or connect() on which queue/cpu a socket is managed. We normally use one cpu per RX queue (IRQ smp_affinity being properly set), so remembering on socket structure which cpu delivered last packet is enough to solve the problem. After accept(), connect(), or even file descriptor passing around processes, applications can use : int cpu; socklen_t len = sizeof(cpu); getsockopt(fd, SOL_SOCKET, SO_INCOMING_CPU, &cpu, &len); And use this information to put the socket into the right silo for optimal performance, as all networking stack should run on the appropriate cpu, without need to send IPI (RPS/RFS). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: move sk_mark_napi_id() at the right placeEric Dumazet2014-11-11
|/ | | | | | | | | | | | | | | | sk_mark_napi_id() is used to record for a flow napi id of incoming packets for busypoll sake. We should do this only on established flows, not on listeners. This was 'working' by virtue of the socket cloning, but doing this on SYN packets in unecessary cache line dirtying. Even if we move sk_napi_id in the same cache line than sk_lock, we are working to make SYN processing lockless, so it is desirable to set sk_napi_id only for established flows. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: fix saving TX flow hash in sock for outgoing connectionsSathya Perla2014-10-22
| | | | | | | | | | | | | | | | | | | | The commit "net: Save TX flow hash in sock and set in skbuf on xmit" introduced the inet_set_txhash() and ip6_set_txhash() routines to calculate and record flow hash(sk_txhash) in the socket structure. sk_txhash is used to set skb->hash which is used to spread flows across multiple TXQs. But, the above routines are invoked before the source port of the connection is created. Because of this all outgoing connections that just differ in the source port get hashed into the same TXQ. This patch fixes this problem for IPv4/6 by invoking the the above routines after the source port is available for the socket. Fixes: b73c3d0e4("net: Save TX flow hash in sock and set in skbuf on xmit") Signed-off-by: Sathya Perla <sathya.perla@emulex.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: clean up cookie_v4_check()Cong Wang2014-10-17
| | | | | | | | | | | | | We can retrieve opt from skb, no need to pass it as a parameter. And opt should always be non-NULL, no need to check. Cc: Krzysztof Kolasa <kkolasa@winsoft.pl> Cc: Eric Dumazet <edumazet@google.com> Tested-by: Krzysztof Kolasa <kkolasa@winsoft.pl> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv4: share tcp_v4_save_options() with cookie_v4_check()Cong Wang2014-10-17
| | | | | | | | | | | | cookie_v4_check() allocates ip_options_rcu in the same way with tcp_v4_save_options(), we can just make it a helper function. Cc: Krzysztof Kolasa <kkolasa@winsoft.pl> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2014-10-08
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: "Most notable changes in here: 1) By far the biggest accomplishment, thanks to a large range of contributors, is the addition of multi-send for transmit. This is the result of discussions back in Chicago, and the hard work of several individuals. Now, when the ->ndo_start_xmit() method of a driver sees skb->xmit_more as true, it can choose to defer the doorbell telling the driver to start processing the new TX queue entires. skb->xmit_more means that the generic networking is guaranteed to call the driver immediately with another SKB to send. There is logic added to the qdisc layer to dequeue multiple packets at a time, and the handling mis-predicted offloads in software is now done with no locks held. Finally, pktgen is extended to have a "burst" parameter that can be used to test a multi-send implementation. Several drivers have xmit_more support: i40e, igb, ixgbe, mlx4, virtio_net Adding support is almost trivial, so export more drivers to support this optimization soon. I want to thank, in no particular or implied order, Jesper Dangaard Brouer, Eric Dumazet, Alexander Duyck, Tom Herbert, Jamal Hadi Salim, John Fastabend, Florian Westphal, Daniel Borkmann, David Tat, Hannes Frederic Sowa, and Rusty Russell. 2) PTP and timestamping support in bnx2x, from Michal Kalderon. 3) Allow adjusting the rx_copybreak threshold for a driver via ethtool, and add rx_copybreak support to enic driver. From Govindarajulu Varadarajan. 4) Significant enhancements to the generic PHY layer and the bcm7xxx driver in particular (EEE support, auto power down, etc.) from Florian Fainelli. 5) Allow raw buffers to be used for flow dissection, allowing drivers to determine the optimal "linear pull" size for devices that DMA into pools of pages. The objective is to get exactly the necessary amount of headers into the linear SKB area pre-pulled, but no more. The new interface drivers use is eth_get_headlen(). From WANG Cong, with driver conversions (several had their own by-hand duplicated implementations) by Alexander Duyck and Eric Dumazet. 6) Support checksumming more smoothly and efficiently for encapsulations, and add "foo over UDP" facility. From Tom Herbert. 7) Add Broadcom SF2 switch driver to DSA layer, from Florian Fainelli. 8) eBPF now can load programs via a system call and has an extensive testsuite. Alexei Starovoitov and Daniel Borkmann. 9) Major overhaul of the packet scheduler to use RCU in several major areas such as the classifiers and rate estimators. From John Fastabend. 10) Add driver for Intel FM10000 Ethernet Switch, from Alexander Duyck. 11) Rearrange TCP_SKB_CB() to reduce cache line misses, from Eric Dumazet. 12) Add Datacenter TCP congestion control algorithm support, From Florian Westphal. 13) Reorganize sk_buff so that __copy_skb_header() is significantly faster. From Eric Dumazet" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1558 commits) netlabel: directly return netlbl_unlabel_genl_init() net: add netdev_txq_bql_{enqueue, complete}_prefetchw() helpers net: description of dma_cookie cause make xmldocs warning cxgb4: clean up a type issue cxgb4: potential shift wrapping bug i40e: skb->xmit_more support net: fs_enet: Add NAPI TX net: fs_enet: Remove non NAPI RX r8169:add support for RTL8168EP net_sched: copy exts->type in tcf_exts_change() wimax: convert printk to pr_foo() af_unix: remove 0 assignment on static ipv6: Do not warn for informational ICMP messages, regardless of type. Update Intel Ethernet Driver maintainers list bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING tipc: fix bug in multicast congestion handling net: better IFF_XMIT_DST_RELEASE support net/mlx4_en: remove NETDEV_TX_BUSY 3c59x: fix bad split of cpu_to_le32(pci_map_single()) net: bcmgenet: fix Tx ring priority programming ...
| * tcp: better TCP_SKB_CB layout to reduce cache line missesEric Dumazet2014-09-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TCP maintains lists of skb in write queue, and in receive queues (in order and out of order queues) Scanning these lists both in input and output path usually requires access to skb->next, TCP_SKB_CB(skb)->seq, and TCP_SKB_CB(skb)->end_seq These fields are currently in two different cache lines, meaning we waste lot of memory bandwidth when these queues are big and flows have either packet drops or packet reorders. We can move TCP_SKB_CB(skb)->header at the end of TCP_SKB_CB, because this header is not used in fast path. This allows TCP to search much faster in the skb lists. Even with regular flows, we save one cache line miss in fast path. Thanks to Christoph Paasch for noticing we need to cleanup skb->cb[] (IPCB/IP6CB) before entering IP stack in tx path, and that I forgot IPCB use in tcp_v4_hnd_req() and tcp_v4_save_options(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * ipv4: rename ip_options_echo to __ip_options_echo()Eric Dumazet2014-09-28
| | | | | | | | | | | | | | | | | | | | ip_options_echo() assumes struct ip_options is provided in &IPCB(skb)->opt Lets break this assumption, but provide a helper to not change all call points. ip_send_unicast_reply() gets a new struct ip_options pointer. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * tcp: avoid possible arithmetic overflowsEric Dumazet2014-09-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | icsk_rto is a 32bit field, and icsk_backoff can reach 15 by default, or more if some sysctl (eg tcp_retries2) are changed. Better use 64bit to perform icsk_rto << icsk_backoff operations As Joe Perches suggested, add a helper for this. Yuchung spotted the tcp_v4_err() case. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit v1.2.1 (git 2.18.0) at 2024-11-09 10:55:06 +0000